The racer sees Sonic and friends racing in cars that also transform for aquatic and aerial travel. That might sound a little familiar to Mario Kart 7 veterans, but developer Sumo Digital has assured fans it's very different: you race on the water's surface, not below the waves, for one.

Confirmed characters so far include the usual cast of Sonic characters as well as Golden Axe dwarf Gilius Thunderhead and Vyse from Skies of Arcadia, Beat from Jet Set Radio and Crazy Taxi's B.D. Joe. There's also a Panzer Dragoon stage confirmed, which gets us very excited indeed.

The racer is so far revealed for 3DS but we'd put money on a Wii U version being announced before too long. Expect more details later today.

LONDON & SAN FRANCISCO – 30th April 2012 – SEGA® Europe and SEGA® of America Inc. are excited to announce Sonic & All-Stars Racing Transformed™, a thrilling new racing experience featuring Sonic the Hedgehog and a fantastic cast of SEGA All-Stars competing across land, air and water in vehicles that fully transform from cars, to planes to boats. Sonic & All-Stars Racing Transformed will speed on to the Xbox 360® video game and entertainment system from Microsoft, PlayStation®3 computer entertainment system, PlayStation® Vita, Nintendo 3DS™ hand-held system and PC Digital Download late in 2012.

Following on from the huge success of Sonic & SEGA All-Star’s Racing™, the characters now have their own unique transforming vehicles designed to take advantage of the varying terrain. The line up on the Sonic & All-Stars Racing Transformed grid sees SEGA favourites – including Sonic the Hedgehog, Dr Eggman and AiAi – return to battle against newcomers that include Gilius Thunderhead of Golden Axe and Vyse of Skies of Arcadia. The brand new dynamic environments and tracks in Sonic & All-Stars Racing Transformed are once again inspired by SEGA’s illustrious gaming history. When the road falls away beneath you in Super Monkey Ball’s Temple Trouble track your car transforms into a boat and speeds down the rivers and rapids, whilst the Panzer Dragoon inspired track, Dragon Canyon, takes you into the sky in complete control of your plane, barrel rolling to out-manoeuvre rivals and obstacles before transforming back in to a car and racing to the finish line.

“Given the fantastic feedback we received from critics and consumers alike for the first game we really wanted to push the boundaries on our follow up game, Sonic & All-Stars Racing Transformed” commented David Corless, Global Sonic Brand Director. "Transforming vehicles allow us to do this – as well as drifting your car around the corners of a track, you get to fly your plane and pilot your boat against others all within one race. Add to this a grid full of star characters, retro IP, fun, fast race modes and cool tracks and racing fans of all ages are sure to love this one!”

Sonic & All-Stars Racing Transformed also sees the popular All-Star moves return with a brand new mechanic allowing your All-Star bar to power up faster if you race daringly and stylishly. An all new fair weapon system ensures that weapons fired at your vehicle can either be blocked or evaded once you have gained the skills to do so, making each race a unique and exhilarating experience whether it’s on water, in the air or on land. Old rivalries can be settled and new track records set in the enhanced online multiplayer mode, whilst the Grand Prix mode and competitive Battle Arenas will prove that Sonic & All-Stars Racing Transformed is certainly set to change the rules of the race.